This summer I did manage to get out and do the Cullin Ridge, a technical scramble with some graded climbing. It was 32 km, 3000m +- and took 19hrs. TrainingPeaks gave a TSS of 600+. This seems extremely high so do you have a very rough idea of what TSS a long mountaineering day like this should give?
You might find this forum topic helpful to estimate TSS for long days on the mountain.